The present invention relates to an airbag system mounted to a vehicle such as a car.
Various airbag systems are generally used for restraining occupants' bodies in a car collision, such as a driver airbag system that inflates and deploys from a rotational center of the steering wheel toward a driver side in a driver seat and a passenger airbag that inflates and deploys from an instrument panel toward a passenger seat side.
One airbag system is a leg airbag system for preventing occupants' legs from colliding with an interior panel and the like in front of the seat and for restraining the vicinity of the knees in order to prevent movement of the lower half of the occupants' bodies toward the front of the vehicle.
The leg airbag system includes an airbag disposed inside the interior panel (in the space on the back of the interior panel), a gas generator for inflating the airbag, and a lid that covers the airbag in a normal state (when the high-speed mobile body such as a car is not in a collision).
Such a leg airbag system may be constructed such that the airbag is disposed in a folded state inside the interior panel, and a lid is mounted so as to cover the folded airbag. When a car, for example, collides head-on with an object, the gas generator generates a jet of gas. The gas is supplied to the airbag to open the lid with the inflation of the airbag, permitting the airbag to expand to an exterior of the interior panel inflating and deploying between the interior panel and the lower legs of the occupant, thereby preventing the occupant's lower legs from striking against the interior panel. Hereinafter, this type of airbag that inflates forward of occupant's legs is referred to as a knee airbag.
One example of the leg airbag system includes a knee airbag manufactured in such a way that a sheet of fabric is folded back substantially at the center. A part of sewing portion of the fabric remains unsewn, and a rim part, except for the unsewn part, is sewn into a bag shape. A gas generator is accommodated in the bag through the unsewn part, and the unsewn part is then sewn with the end of the gas generator adjacent to a connector projected from an insertion opening of the bag (refer to, for example, Japanese Unexamined Patent Application Publication No. 2003-40071 (p. 5, FIG. 5).
The above prior art discloses a basic structure of a leg airbag system including a knee airbag and a gas generator passing through the insertion opening of the knee airbag.
The present disclosure provides an airbag system in which the deployment performance of an airbag may be improved by improvement in air tightness.